Analysis of enhanced effects in MSSM from the GUT scale Fermilab, 5/19/2006 Analysis of enhanced effects in MSSM from the GUT scale Enrico Lunghi Based on: E.L., O. Vives, W. Porod, hep-ph/0605177
Outline MSSM with Minimal Flavor Violation at the GUT scale The observables: Results
The MSSM We impose R-parity to avoid problems with proton decay and to have a dark matter candidate (LSP) The SUSY conserving part of the MSSM lagrangian depend on the same parameters as the SM analyticity of the super-potential requires 2 Higgs doublets the vev’s can be chosen independently: a mixing term is allowed: The soft-breaking terms introduce ~120 new parameters: superfields scalar fields
Minimal Flavor Violation We adopt the definition of D’Ambrosio, Giudice, Isidori & Strumia. The only relevant information contained in the quark Yukawa’s are the eigenvalues and the CKM matrix: where the matrices UR, DL and DR are unphysical. This definition is RGE invariant and can be imposed in terms of an exact additional flavor symmetry The structure of FCNC’s follows the CKM pattern In large tan scenarios, integrating out the SUSY spectrum results in sizable corrections to dim·4 operators: large (huge) effects on and
Minimal Flavor Violation @ GUT scale Most analyses are done at the EW scale We want more “realistic” models and consider the MFV MSSM with GUT unification: mSugra most general model (referred from now on as MFV) At this time we do not include any new phase, but there is no impediment to do so, still remaining in a MFV framework.
Minimal Flavor Violation @ GUT scale We introduce the soft-breaking terms are at the GUT scale we require gauge coupling and gaugino mass unification: The rest of the soft-breaking terms is defined as: In the mSugra case we have: We scan over:
Minimal Flavor Violation @ GUT scale We use Spheno [Porod] to run the 2-loop RGE’s for the MSSM fully including generation mixing and large tan() resummation (most up-to-date machinery; not public) Fix (at 2 loops) by requiring Radiative-EWSB At the low-scale we impose constraints from direct searches the -parameter neutral LSP h2 perturbativity of the yukawas between the EW and GUT scales b ! s muon g-2 Bs ! Bs mixing
Higgs-mediated FCNC The -term in the superpotential induces non olomorphic higgs interactions and introduces tree level Higgs-mediated FCNC’s: After EWSB this lagrangian results in: In the quark mass-eigenstate basis we have (S=h,H,A):
The most important operators are: They both receive similar contributions by tree-level exchange of heavy Higgses with one flavour changing Higgs insertion: The branching ratio is: The experimental bound and the SM theory predictions are:
The dominant contribution stems from double penguin diagrams: The Bs mass difference is given by: The double penguin contribution is always negative The measurements reads: The SM prediction is:
The dipole operators are: W and charged Higgs contributions are both negative. The sign of the chargino one is given by –sign(At ). Since At at the EW scale is dominanted by –M1/2, we have destructive and constructive interference for >0 and <0, respectively The world average is: The SM prediction is:
Muon g-2 The dominant contribution comes from the chargino-sneutrino diagram: the sign of SUSY contribution is therefore, sign() Complete theoretical predictions are complicated by non-perturbative QCD effects: light by light scattering hadronic contribution ! can be extracted by data on ee and data (the latter up to isospin corr.) Experimental and theoretical results read: (problematic)
Dark Matter In the MSSM with R-parity, the lightest neutralino is stable and provides an excellent dark matter candidate We use the program micrOmega to implement the calculation of the relic neutralino density Experimental results (WMAP data) are extremely good: Unfortunately the theoretical situation is much cloudier: parametric errors (e.g. Mt) and uncertainties in the RGE running from the GUT to the EW scales (especially in the large tan region) impact strongly the calculation of h2 Moreover, points for which h2 is too small can always be “saved” by some other dark matter candidate In view of these remarks, we take a conservative attitude and impose only a loose upper bound:
Results mSugra vs MFV dark matter scenarios impact of a large on collider phenomenolgy
gray: excluded by FCNC data orange: opposite sign for the b! s amplitude
gray: excluded by FCNC data orange: opposite sign for the b! s amplitude
gray: excluded by FCNC data orange: opposite sign for the b! s amplitude
gray: theory errros on MBs line: measurement
mSugra: dark matter scenarios gray: excluded by FCNC data orange: A-pole region ( ) black: stau coannihilation region ( )
MFV: dark matter scenarios gray: excluded by FCNC data black: stau coannihilation region ( ) orange: A-pole region ( ) red: Higgsino dominated neutralino ( >5% )
MFV: Higgsino domination The neutralino mass matrix is: The lightest neutralino is higgsino dominated if: In models with GU and REWSB we have: So the LSP is higgsino dominated if
MFV: Higgsino domination
Large phenomenology orange: all constraints imposed black:
Summary Full scan of parameter space of MFV models with Grand Unification, using most up-to-date technical tools Interplay vs Dark matter scenarios (Higgsino dominated neutralino) Large tan phenomenology